The leanest medium. Ready to use straight from the container. Dries overnight, depending on climate and thickness of paint application. Art Spectrum Painting Medium No. 1 contains a balanced amount of Stand Oil and turpentine for a well-balanced, permanent paint layer. Often an excessive amount of gum turpentine is used as a substitute for a ‘lean’ medium. Too much gum turpentine ‘denatures’ the oil paint in these lean layers. This leaves an underbound pigment when the paint dries which weakens the bond between the oil paint and the canvas. Also useful to clean and lessen absorbency of pre-primed canvas panels and stretched canvas (wipe on and wipe off).